OS/2 C-Kermit 5A(191)

FAST 32-Bit Native Communications Software for OS/2 2.x and WARP

NOTE: OS/2 C-Kermit is obsolete. It is replaced by
Kermit 95 for OS/2. The remainder of this page
is kept for historical reasons. Kermit 95 for OS/2 has all of the
features described below, and many more.

CONNECT mode -- terminal emulation -- is now incredibly fast and snappy on both
serial and network connections, in both window and fullscreen sessions.

C-Kermit 5A(191) processes incoming data in parallel with screen updating.
Furthermore, the screen is now updated far more efficiently than before.
To give an idea of the speed improvement, we used a ripple-test benchmark
that scrolls 1000 80-column lines of text, obtaining the following display
timings for various TELNET clients attached to a 10 Mb/sec Ethernet
network running on the same PC in a fullscreen session:

In an OS/2 window, the same test takes only 7 seconds, compared to 55
seconds in the previous release -- about an 800% improvement.

The new display management model has also been used to accomplish several
other astounding feats:

Terminal sessions remain active behind popup help screens.

Incoming material is processed even when screen is rolled back.

Copy-and-paste can span multiple screens (more about this below).

Meanwhile, serial port handling is now far more efficient, putting less load
on the CPU, allowing serial-port input/output to take place at high speeds
without seriously impacting the rest of the system.

You asked for VT100 132-column mode, now you've got it and a lot more too.

In Warp window sessions, C-Kermit now supports any combination of screen
height and width, up to 255 columns and 254 rows with a maximum screen
area of 8192 characters.

In fullscreen sessions the terminal screen can now use 40, 80, or 132
columns and 24, 42, 49, or 59 rows. Not all combinations are supported by
all video hardware. Warp is not required.

Host-directed screen-width switching in VT100, VT102, and VT220 emulation
is now implemented for 80-column and 132-column modes when the video
adapter supports it. Screen dimensions are automatically reported to the
host on TELNET connections if the TELNET server supports (and uses) the
"NAWS" option.

C-Kermit 5A
knows a lot of character sets
and translates between any pair of them. But in OS/2, we have another
problem: how to see the right characters on the screen. For example, in
version 5A(190) we added support for Hebrew terminal emulation, which works
very nicely if you happen to have a Hebrew version of OS/2 (which you can only
get in Israel), but is useless otherwise -- e.g. to Hebrew and Yiddish
scholars in the USA, because, until now there was no way to get a Hebrew code
page onto a US version of OS/2.

The new version of OS/2 C-Kermit comes with the following soft fonts that
you can load in a fullscreen session, for use in the terminal window:

OK, we added a Cyrillic font, so now you can read those Russian newsgroups
and Web pages. But if you don't have a Russian (or Ukrainian, or
Belorussian) keyboard, how do you TYPE Russian characters? The new
C-Kermit release adds a Russian keyboard mode that includes:

The Microsoft Russian DOS keyboard layout.

Hot-key switching between Russian and English modes.

Automatic translation to the host character-set (KOI, ISO, etc).

This is in addition to the keyboard methods that were already available
in earlier releases:

A Compose key for Latin-1-like character sets (for Western European
languages like Italian, Portuguese, Norwegian, German, French, etc).

TELNET connections are about 500% faster than before. Several TELNET
protocol problems were fixed, most notably the ones relating to
"firewalls". Connections are now attempted to multiple IP addresses when
provided by the name server, until success is achieved. TELNET NAWS
(Negotiate About Window Size) capability has been added.

Incoming TCP/IP connections are now accepted -- you can TELNET to OS/2
C-Kermit on a pre-arranged socket and have a "chat" session or execute
Kermit server functions.

OS/2 C-Kermit can now dial your Warp IAK SLIP connections for you, using
a special technique to "borrow" the serial port from the SLIP driver.
This gives you a lot more flexibility than you get with SLIPTERM.

There are new controls for TELNET NVT/binary mode and CRLF mapping, since
these areas are so problematic with the proliferation of incompatible
(and often confused) TELNET servers:

OS/2 C-Kermit gives you all the convenience features of a serial
communications program integrated with its own internal TELNET protocol
implementation. If you do a lot of TELNET'ing to diverse services,
especially on non-TELNET ports, you'll begin to appreciate what this
means. If you want it spelled out in more detail, see the
APPENDIX at the end of this announcement :-)

System Sounds can now be used to differentiate "Information",
"Warning", and "Error" events.

REMOTE RENAME and REMOTE COPY (both ends) added.

Various other new commands, bug fixes, cleanups, etc.

DOCUMENTATION

OS/2 C-Kermit 5A is comprehensively and professionally documented in the
book, Using C-Kermit, supplemented by the hypertext CKERMIT.INF
file, which covers recent additions up to and including edit 191.

If you will be using OS/2 C-Kermit and you have not already purchased this
book, please purchase it. It will answer your questions,
it will show you how to get the most out of the software, and book sales
are the primary source of funding for the Kermit effort.

Ordering information for Using C-Kermit is
included in the CKERMIT.INF file, which may be accessed from the C-Kermit>
prompt with the UPDATES command, and is also available by
CLICKING HERE.

Your serial communication package MIGHT enable you to connect to your host
this way, but if it works right throughout your session, it's pure luck.
Numerous items -- echoing, screen size, terminal type, and other
parameters -- need to be negotiated and sometimes changed dynamically
throughout the session, depending on the service and the server.

A serial communications program is not designed to handle this type of
work. So the virtual modem software must handle the TELNET protocol
parameter negotiations on behalf of the communication software. So far,
so good. The problem is that when things change, the virtual modem
software has no way of telling the communications software, and similarly,
when the user changes things in the communications software, the virtual
modem doesn't find out about it and can't tell the TELNET server.

To complicate matters further, the TELNET Network Virtual Terminal (NVT)
definition does not work like the ASCII terminal that your serial
communications software is emulating. Certain characters must be handled
specially, including carriage return, linefeed, and the "all-ones"
character, hex FF. Furthermore, special items like the BREAK signal must
be handled by special TELNET protocol messages.

So when using serial communications software to accomplish a TELNET
connection over a virtual modem, you are very likely to experience all sorts of
problems, including:

Terminal-type and/or screen-size mismatch.

Faulty echoing: characters can fail to echo when you type them, or
might echo twice. "Password silencing" might not work.

You might get overprinting or a "stairstep" effect as the host sends
lines to your terminal screen.

Carriage return (Enter) might have no effect at all when you type it.

A carriage return might result in two blank lines.

The session might suddenly hang because a special character has not
been properly escaped during terminal emulation or file transfer.

BREAK, required by some hosts and applications, can't be sent.

When things go wrong, you have no effective debugging tools at your
disposal, and even when you can diagnose the problems you often have no
way to fix them.

THE MORAL: If you want a fully-functional and dependable TELNET
session, use a real TELNET client. If you want to use the same software
for both serial and TELNET connections, try C-Kermit.